Need help to create checkbox limits per column

[mantiscore]

Hello,
I am working on a matrix.
I have checkboxes in all cells of the matrix, and based on that a calculation is made. However i need something to limit the filled checkboxes to one per column. Is there any way i can do it?
Thanks in advance, if more information is needed im happy to provide it quickly.

 

[Kaper]

Are the checkboxes joined with cells? Then you could use COUNTIF function to alert user (for instance with conditional formatting) that There is more than one in given column.

The second possibility is to use VBA and in the code of a given sheet use Change event handler to analyze after any change of cell value in a workbook (or a range) if more than one value in a column is TRUE and if it is - display a message and UnDo last change.

 

[NoSparks]

You could use Form Control checkboxes and use the .OnAction property
so they all call the same macro that could be along the lines of this

Private Sub RunForMatrixChkBoxes()

    Dim col As Long

With ActiveSheet.CheckBoxes(Application.Caller)
    col = .TopLeftCell.Column
    If Application.WorksheetFunction.CountIf(Columns(col), True) > 1 Then
        MsgBox "This column already has a checkbox checked" & vbLf & _
               "Will uncheck that last one"
        .Value = False
    End If
End With

End Sub